Apparatus for taking samples of molten metal

ABSTRACT

A sample of molten metal is taken by swinging an elongate arm over the molten metal from a safe distance and by lowering a carried sampling tube into the molten metal to extract a sample. The sample-containing tube is raised and swung to a collecting station, where it is released. The sampling arm is pivotally mounted to swing on a vertical axis and has a receiving clamp at its free end for holding an evacuated sampling tube. Means are also provided for lowering the sampling tube into and lifting it from the molten metal. Individual empty sampling tubes are successively inserted into the receiving clamp by injecting mechanism located at a work station a safe distance from the molten metal but within the lateral swing path of the free end of the arm. The tubes are individually supplied to the injecting mechanism, preferably from storage, by dispensing mechanism. The apparatus can be programmed to execute its sampling cycles automatically at desired frequency, and is preferably mounted upon a movable platform for convenient placement with respect to molten metal to the sampled.

1451 Feb. 1, 1972 APPARATUS FOR TAKING SAMPLES OF MOLTEN METAL Primary Examiner- S. Clement Swisker Attorney-John L. Sniado and Mallinckrodt and Mallinckrodt A sample of molten metal is taken by swinging an elongate arm over the molten metal from a safe distance and by lowering a carried sampling tube into the molten metal to extract a sample. The sample-containing tube is raised and swung to a collecting station, where it is released The sampling arm is pivotally mounted to swing on a vertical axis and has a receiving clamp at its free end for holding an evacuated sampling tube. Means are also provided for lowering the sampling tube into and lifting it from the molten metal. Individual empty sampling tubes are successively inserted into the receiving clamp by injecting mechanism located at a work station a safe distance from the molten metal but within the lateral swing path of the free end of the arm. The tubes are individually supplied to the injecting mechanism, preferably from storage, by dispensing mechanism. The apparatus can be programmed to execute its sampling cycles automatically at desired frequency, and is preferably mounted upon a movable platform for convenient placement with respect to molten metal to the sampled.

ABSTRACT 10 Claims, 9 Drawing Figures .P E m 31638500 SHEET 1 0F 4 INVENTOR. MAYO R. WETZEL ATTORNEYS PATENTED FEB 1m 3,638,500

sum 2 or 4 summi' INVENTOR. MAYO R. WETZEL AT TORNE YS mzmeum uwz 3.838.500

ATTORNEYS APPARATUS FOR TAKmo SAMPLES F MOLTEN ME BACKGROUND OF THE INVENTION l Hem .QBJEGTIVES fli pri'mai'y objectiveih the ma kin gof this i pvedt ioniwas to providefor vie lunge: samples ofmeta ljv vhile still molten but withoiiidangfer oripjq y "rkr'x i en; preferably to do this autdinaticaily at predetei'l ed time intervals so as to ef-' fect savings in manpower and enabletheobtaining of uniform samples.

SUMM RY OF THETINIVEN'IZION T e Wh t-upset hjnvent qn inmudess p g rm x tending laterally ftompivptgl afiflehment to a support, "so that it an besyvupg at l ast l aterallyl reletiveitmthe support: The" arm is e'qui ppedat free endlwithmeans tpn neeeiving and holding repiaceabie samplipgig Lubes, preferably nevaeuated glass tubes, Means grepropgidpdfont ipping the held sampling tube into the niolten metal tmbmsampledand fora-withdrawing the tube tiftmjqfwmwfidditifinalpneans are provided for raw: ing a held tube following the taking of a sample, as are means for r epla cingempty sampiing mbes in theholdingin eans. A motor orot h ep-driying 'mechanism islused to swing the sat'fipling arm awimmme su pnt: and? limirlsuiitehesor the like are provided topogtro tmetlqngthpfzthetpivot-arcf The means for ir ei acingtempty-sampling tubes i's re'ferablydisposed below lthfi tube-holdingmieans ava Work station located a safe distgneefrom theimdten trie'tal'it'o'-l5eiian1i5led but within the swingwpath ofsueh iube-hbidhig lfltetii'fik The tube-homing means eom'prises irijector Wehahisiihfdr preferably feeding indivjduai'sampiing-tubes vertically Hit? the tube-holding means; a eontainer'fofla plttrality oieri'tpt y sam pling tubesel and mechanismfor continuously feedifig lh dividua .iubes. from'the container-into lhe-injeetormecfia isiwi For ease ofttxansportation an'dpecisepositioningof the ap paratus with eespect to then'iolten' metal; itisadvaitta'g e olj' mount the Sampiingnili'm flfid the tube-inserting 'm'ee iiis c:

movable platform or frame. A v

In practjfieathczappafatustis positidned neaithe sainpliii'g ibcation, so that support ahd= tiYbe insefting ini aii sii'are; located a safe idistancefib'r'ri the molt tifmetalf The arm isit n swung around lthe lsupport td pllic the-"ttt oe -hiiitii ii and sampling tube at k predteflhirldjabsifib fiivetftfitf n i ten metal to be sampled, and a sample is taken by loti/e tube into the molten meratvtminfipfie filled 2W1 g arm to a sample-dolieiitinfi'siiitioniaitd t i V a I L 1 its contained sampieFThu's, sensitive eqri't'rdl eomp qnents of the equipment are not subjected to the hightempera'tpre metal splash which are presentin the area immediately sul a rounding the molten meta l be itig sampled 1- 2 11M DESCRIPTION OF THE'DRAWINQS An embq n emmf apparatug constitqting the: best mode presentl'y contemplated of carrying out the invention is shown in the accompanying drawings, in whieh;

FIG. I is a fragmentary top plan view sh owing the apparatus positioned aie'ana casting v'vheel iofmo lpn with the sampling arm eit'telidiil over a 56m to be sampledfbut in- 'dieatedby dbtte'dliriesmitssta" ng e'ttirh,positions; 7 no; z aside-elevation imagin -fro m ligjei lji-lq. i. and showing the paiams per 5%: I

FIGS 3', a transveise se tio ri through the apparatus taken atong'the fin 3- 3 at Fio. 1: sho uiit'tlie srh'pligg mi in elevation:

F1637, it lonzitudifiarveltical'seCtiohtaken, along the line 7-mofFlG. 6*}

' F'lG'i-B; a traiisvers e vei'tie'al sectionitaltenalpng the line 8-, 8 of Fio: 1', and

FIG; 9,-a' schematic Wiring diaggam t an automated emhodim'iii'ofthe apparatus; 4

DETAILED oEsemPTioN OFTHEEIELUSTRATED eivtaobm'qizrin As illustrated the sevel al mec hgnismsincluded in-th apparatus of the invention are advantageously moulited on a movable, platform 10 for ease ofiplacemen-t and reniovali eiative to the molten metaito be sampled, which is'here shown, FlGl 1, asa plurality of pools Aofmoltemcoppet case' ineustomary manner in respectiveanodemolds of a circumferential se rie ofsame carried by a conventional anode casting wheel wlutillieed iii-the Pm uetion'ofcastcop penanddsfor an 'leelyti wpp r efinin -l rfi s ttppprtjptheform qfapos-t fl having -an upwardly projeqtipg rotatable shaft- 1 la, istncuntedonthe 'platforiii10', aiid a sampiipg arm 1,1 ivotally attached tmrhe top bf fh'e'post on a ggtiggi M5591 Aviation, p'rovidediihy sh al t lil1',st a to extend lateraliypfithe (post anditoipivot ln at? aretfiei eai'fiuhti'.

in this illustrated embodiment, arm 12 is balanced on a iballastlorlcounterweight lfi whidh is chewed in'a wage "i810 rot ct it, dram inteefe-rehce during the "st/main? is? ariiii 2Q Cage lt'qjs seeugelymounted on platform 1-16;

The meansfon holding individual samp lingtiibes is lqeated at the treeend ot the arm 1-2 nukes-shown; temehafiryi ata tithe-glam lflhavingra stafiohat y aw m ands iiievable 17b pivoted at 11. The clamp lmis 'h'itl'iniilesifieliiiifpihfi position by, a spring lB, see "espeeia-iiy FiG: *AW'iifitmnneets movahlq jaw 41:71: above ite pivo tptiinttiia sdl en oi'c l 119p whiehis, aqtiv ated 2m pull th ewire'and niereis' bpeh' rfiela ni 17 foreither releasing a filled-tithe er tee'eivingaiiempt'ftiibef Dgive mechanism is attaohdd to tfie postl-l l rsifirigifig the arm 12 from a work station WS on the platform to a predetetm-ine'pusitioti over the when ii1et'al jta'iie sampled and baiek to the. wmrk station-afte'rthe'siimpl e has been taken.

Operation'of-driv e mechanism is controlled by three limit switchesas, 26g andi7locat'edabout the stat onary portion 'of post llx'lwo of the switches, 25"anci'26 define the arc traversed by the free end ofarm l2from the w rk station WS to theipredetermined position hveifthe molten metal to sampleds 'l'he' third when, 2.1;- is a mime; svviibifwiiieli activates clamp-solenoid l9aduridg the retlurn sflin ,ofarlm 12 to open tube ciamp l7 antiielia'se the filled kimpiimb at tube-collecting station, preferably a funnel 28 emptying into a catch receptacle 280, here shown as located at work station WS. The three switches 25, 26, and 27 are activated by trigger members 29, 29a, and 29b, FIG. 4, which are attached to and for circumferential adjustment about shaft lie of post 11. In operation, as shaft Ila rotates to swing arm 12 over the mol ten metal and then back to the work station, trigger members 29 and 1290 contact first one and then the other of switches and 26 respectively to limit the arcuate swing. During the return swing of arm 12, trigger member 29b actuates knee-action switch 27 to release the held sample tube into funnel 28.

In addition to swinging laterally about post 11, arm 12 in this illustrated embodiment swings vertically about the horizontal axis provided by pivot pin 13. When arm 12 is in position to take a sample from the molten metal, as shown in FIG. 2, it is swung downwardly to lower its free endequipped with tube clamp l7and to dip the empty sampling tube held thereby into the molten metal. This is accomplished by activating dipping mechanism mounted on a lateral extension [40 of bracket 14. The dipping mechanism comprises a lever arm 30 connected by a link 31 to sampling arm 12. Lever 30 is connected to drive mechanism 32, which may be an electric motor controlled by limit switches 33 and 34 adjustably mounted in an arcuate slot 35 so the length of vertical swing or dip of arm 12 can be varied to suit different levels of molten metal positioning.

Although in this illustrated embodiment the am 12 is swung down to dip the sampling tube into one of the molten metal pools A, the arrangement can be such that tube clamp 17 is lowered independently of the arm 12 for the purpose.

A vertically adjustable support in the form of a post 36 is mounted on platform 10 at the work station WS and serves to support means for replacing empty sampling tubes in the tube clamp 17. Such tube-replacing means includes, in this embodiment, a tube injector mechanism 37, a container 38 for holding a plurality of empty sampling tubes 39, and a mechanism 40 for feeding individual tubes from container 38 into the injector mechanism 37, all as shown in detail in H68. 6, 7, and 8.

The several components of the tube-replacing means are advantageously mounted on a horizontal supporting surface 410 provided by a platform 41 and disposed below the level of tube clamp 17 when such tube clamp is positioned at work station WS. The platfom 41 can have side panels 41b extending upwardly and a top (not shown), if desired, to protect the components from dust and heat. lf side panels 41b are included, an opening 4lc in the side panel over which tube clamp 17 passes in its swing from the work station W8 must be provided to permit the empty tube held by the tube held by the tube clamp to pass therethrough.

The container 39 for holding a plurality of sampling tubes has an elongate channel 42 for holding a plurality of empty, upright sampling tubes 39, preferably evacuated glass sampling tubes, in linear alignment with tube injector mechanism 37 disposed at one end of channel 42 under the supporting surface 4la.

In the illustrated embodiment, the mechanism 40 for feeding empty tubes 39 into the tube injector mechanism 37 has a semicircular flange 43 adapted to fit around one side of a sampling tube 39. The flange is disposed within channel 42 behind the last tube 39a in the channel and urges the tubes 39 forward within channel 42 individually into an injection zone 44 disposed at the end of the channel directly above injector mechanism 37 and below tube clamp 17. Means attached to flange 43 for urging the tubes forward includes herein a conveyor carriage 4S fixably attached to flange 43 and adapted to move along a rod 450 disposed adjacent to, and extending along the longitudinal side of channel 42. Conveyor 45 is secured to a reciprocable chain 46 which is connected at one end thereof to a sprocket 47 and at the other end to a drive sprocket 48. Drive sprocket 48 is, in turn, connected with a reversible electric motor 49 mounted on the supporting surface Me. As flange 43 urges the foremost tube 3% into injection zone 44, the tube 39b contacts a limit switch 50 located at the extreme end of the injection zone, which shuts off the power to conveyor 45 and stops the forward movement of the tubes. When the last tube in channel 42 has been injected into tube clamp 17, a trigger member 45b attached to conveyor 45 strikes a limit switch 45c at the entrance to injection zone 44. The closing of limit switch 45c reverses motor 49 and moves conveyor 45 to the opposite end of channel 42 to permit the channel to be replenished with empty tubes.

The injector mechanism 37 for moving tube 39!; from tube injection zone 44 upwardly into tube-holding clamp 17 above includes in this embodiment a rod 51 which extends from the underside of the supporting surface 410 through an aperture 52 therein and contacts the bottom of tube 3%. Rod 5l is connected at its lower end to a cam follower 53, which is in turn connected to a rotating cam 54 driven by an electric motor 55, all attached to the underside of platform 4! by means of a pair of downwardly extending support rods 56. As rod 51 rises and inserts tube 39b into the open tube clamp 17, rotating cam 54 is in the upper portion of its arc and closes thereat a limit switch 57 attached to a securing plate 560 which is mounted on rods 56 and is adapted to be vertically adjustable on the rods. The closing of limit switch 57 closes tube clamp [7, thereby securing sampling tube 3% therein. As cam 54 continues to rotate, it closes a momentary switch 58 attached to support rods 56, activating an arm pusher mechanism 59 attached to supporting surface 41a adjacent to arm [2 and adapted to move the arm laterally away from its rest position over injector mechanism 38. The closing of momentary switch 58 also breaks the current to an electro magnet 60 releasing arm 12 from contact with electro magnet 60 which is adapted to hold arm 12 in position over tube injector 37 during the injection of an empty tube into tube clamp 17. Cam 54 continues to rotate and rod 51 drops until the cam closes a lower limit switch 61 mounted on a securing plate 56b, which stops cam 54 with rod 51 at its lowest position below injection zone In operation, work station WS mounted on movable platform 10 is positioned a safe distance away from the molten metal to be sampled, but within the arcuate swing of arm 12. Tube clamp 17 receives an empty sampling tube from injector mechanism 37 as described above, and arm [2 swings outwardly from the work station WS over the metal to be sampled. As the sampling tube held by tube clamp 17 reaches its proper position over the molten metal, the dipping mechanism is activated to lower the end of arm 12, enabling the lower end of the sampling tube to penetrate the surface of the molten metal. The evacuated glass tube is pierced by the hot metal,

and the metal is drawn up into the tube where it solidifies The dipping mechanism then raises the tube out of the molten metal, and arm 12 begins its swing back to its initial position at the work station. Before arm 12 reaches the work station, tube clamp 17 preferably releases the filled sample tube into funnel 28 disposed near the work station. Funnel 28 preferably is connected to a container of cold water 28a into which the filled tube drops. The cold water shatters the glass, leaving the metal plug for analysis. Tube clamp 17 then continues on to the work station, where it is available for the injection of another empty sampling tube and the initiation of another sampling cycle.

The apparatus can be operated manually or can be connected to a power source, such as electricity or compressed air; and can be programmed to operate automatically with timed sequencing of the desired steps in the cycle. FIG. 9 illustrates a circuit diagram for electrical programming of the apparatus for automatic sampling operation.

The automatic operation of the sampling arm is begun by connecting the circuit 62, 62a, 62b to an outside source of energy, preferably a [10 volt line, and closing the power switch 63 permitting the current to flow through a fuse 64 and to activate a pilot light 65. A pushbutton 66 is depressed to permit current to flow through line 67 to energize the relay coil R-l. Energizing coil R-l sends current through lines 68,

69 to close R-l contact 70 and Rl contact 71, which starts the Timer No. 1. Timer No. 1 times out to close Timer No. 1 contact 72, permitting current to flow through line 73 to energize the coil 74 of the drive motor 75 for the outward swing of the sampling arm from the work station. Meanwhile, the clutch 75a has been engaged by the flow of current through line 76 from the direct current power supply 77, which was energized through line 78 and the Timed Delay Relay No. 1 switch 79 when the circuit was energized by closing power switch 63.

When the sampling arm has reached the end of its outward swing over the molten metal to be sampled, the arm closes a limit switch 80, which opens R-5 contact 81 and R6 contact 82 through lines 83, 84, respectively, and energizes relay coil R-2 and relay coil R-3, while opening R-3 contact 790, to deenergize coil R-l. The energizing of coil R-3 disengages the clutch 75a by opening R-2 contact 85, and engages the brake 86 by closing R-2 contact 87. At the end of the outward swing, the dip motor 88 is activated to lower the arm, and the internal switch 89 is closed through line 90 and R-3 contact 91, which was closed by the energizing of coil R3. As the sampling arm reaches the predetermined lower position for sampling the molten metal, it closes an external limit switch 92 sending current through line 93 to activate Timer No. 2. Timer No. 2 determines the length of time that the arm remains down in the sampling position. When Timer No. 2 times out, it closes R-4 contact 97, and energizes relay coil R-4 and relay coil R-S by closing Timer No. 2 contact 94 through the closed limit switch 95. At the same time, coil R3 is deenergized by opening R-6 contact 82 and closing R-5 contact 96. The dip motor drives the arm upwardly through the closed contact 98 until the internal switch 89 of the dip motor 88 has been broken by the opening of external switch 92, thereby stopping the updrive of the motor.

With the opening of the external limit switch 92 the circuit is completed through line 99 to relay coil R-6 preparatory to returning the arm in a reverse swing to its initial position at the work station. R-6 contact 100 is closed to start the drive motor 75 through its reverse coil 101. At the same time, coil R-2 opens R-6 contact 81 which disengages the brake 86, and contact 87 closes to reengage the clutch 750.

As the arm swings back toward the work station, it strikes a momentary switch 102 which energizes coil R8 and coil R-9. Relay coil R8 is held in a closed position through relay coil R-9, the tube limit switch 103, and the closing of R43 contact 104. At the same time, R-8 contact 105 closes to energize the tube clamp solenoid 106 and the tube guide coil 107, which opens the tube clamp and releases the filled sampling tube into a receptacle. In addition thereto, the R-8 contact 105 energizes an electromagnet 1070 which holds the arm in stationary position when the arm strikes the limit switch 95. When the limit switch 95 is contacted by the sampling arm it reverts to the open position and closes R-9 contact 108 through line 109 to energize coil R-7 and coil R40. At the same time coil R4 and coil R5 are deenergized. The energizing of coil R-7 opens contact 110 ofcoil R-7 to disengage the clutch 75a, and closes contact 111 of coil R-7 to engage the brake 86, thereby stopping the arm.

As coil R- is energized, R-10 contact 112 opens and the tube injector motor 113 begins to operate to raise the injector rod with an empty sampling tube. The bottom limit switch 114 on the tube injector closes to hold in coil R-7 and coil R10. At the same time contact 115 of coil R-10 closes, thereby starting Timed Delay Relay No. l, and contact 116 of coil R-10 closes to energize the three-quarter travel limit switch 117 through line 118 and the normally closed timer switch 79 ofTimed Delay Relay No. l.

The tube injector rod strikes and opens the top limit switch 103 to deenergize coil R8 and coil R-9, thereby clamping the sampling tube in the tube holder and deenergizing the electromagnet 107a. R-9 contact 108 opens to break the current from the limit switch 95 to coil R-7 and coil R-lO. The tube injector strikes and closes the three-quarter limit switch 117 and the timer switch 79 of Timed Delay Relay No. 1. The current to the direct current power supply 77 through line 78 is momentarily broken, which releases the brake 86 and simultaneously engages the solenoid 119 for the arm pusher to push the arm away from the electromagnet 107a. The three-quarter limit switch 117 opens when the timer switch 79 of the Timed Delay Relay No. 1 reaches the open position, which drops the current from one side of the winding of the tube injector motor 113 through R-10 contact 115. Tube injector motor 113 then drives the injector rod to the bottom limit switch 114, thereby breaking the contact and applying current to the winding of the tube injector motor 113 through R-10 contact 112 to stop the motor. The unit is now in a standby position ready for the next signal, by manual or remote control, to re peat the cycle.

The mechanism for feeding individual tubes from the con tainer to the injector mechanism requires periodic reloading to replenish the supply of sampling tubes in the lateral channel of the tube container. The automated embodiment provides for retraction of the tube conveyor in the channel when the last tube has been injected into the tube clamp at the end of the sampling arm.

As the last tube is injected into the tube clamp, a microswitch 120 located in the tube injection zone opens because no tube is in the injection zone. The opening of the microswitch 120 starts a Timed Delay Relay 121. When the Timed Delay Relay 121 times out, it breaks the contact 122 energizes the forward motor winding 123 to drive the tub: conveyor forward. The tube conveyor strikes and closes a microswitch 124 located at the entrance of the tube injection zone, which energizes relay coil R-11. At this point the green pilot light 129, which is on during normal operation, is extinguished and the red pilot light 130 is illuminated. The energizing of coil R11 closes R-ll contact 125 and starts 'he current in the reverse winding of the motor 126 by breaking R -11 contact 127, which also drops the current on the forward motor winding 123. The motor drives in reverse until the tube conveyor strikes and closes a third microswitch 128 located at the opposite end of the lateral channel. The closing of the microswitch 128 energizes the forward winding of the motor 121 and stops the reverse drive of the tube conveyor. The channel can now be loaded with sampling tubes.

The tube feeding mechanism remains in standby position until a pushbutton 131 is depressed to activate the mechanism. Depressing the pushbutton 131 deenergizes coil R-11 by closing R-11 contact 127 and opening R-11 contact 132. The reverse winding 126 of the motor is thereby dropped out and the energized forward winding 123 drives the conveyor forward until the forward tube strikes and closes the microswitch 120 in the tube injection zone. The closing of the microswitch 120 energizes the reverse winding 126, thereby stopping the forward drive of the motor and tube conveyor. With a tube in the injection zone, the conveyor is on standby until the tube injector rod lifts the tube into the tube clamp. At this point, the microswitch 120 opens and starts the Timed Delay Relay 121. As the Timed Delay Relay 121 times out, it opens the contact 122 and causes the reverse motor winding 126 to be dropped. The energized forward winding 123 drives the conveyor forward until another tube is pushed into the tube injection zone, thereby closing the microswitch 120 and stopping the forward movement of the conveyor until the tube in the injection zone has been injected into the tube clamp at the beginning of the next cycle.

1 claim:

1. Apparatus for taking samples of molten metal, comprismg a support adapted for positioning between the molten metal to be sampled and a work station at a safe distance therefrom;

an elongate arm extending from and secured to said support for pivotal movement thereat about a vertical axis, so said arm can be swung back and forth between the work station and said molten metal;

sampling tube-holding means carried by the extended end of said arm;

means for swinging said arm about said vertical axis;

means for lowering and raising said tube-holding means with respect to the molten metal to be sampled; and means for releasing filled sampling tubes from said tubeholding means.

2. Apparatus as set forth in claim 1, wherein the means for lowering and raising the tube-holding means comprises a pivotal mounting for the arm on the support for pivotal movement thereat about a horizontal axis, and means for swinging said arm about the horizontal axis.

3. Apparatus as set forth in claim 1, wherein the support comprises an upright post,

4. Apparatus as set forth in claim 1, including means at the work station for successively feeding empty, individual, sampling tubes into the tube-holding means.

5. Apparatus as described in claim 4, wherein the tube-feeding means comprises in combination, a tube-injector mechanism for injecting tubes into the tube-holding means, a container for holding a plurality of empty sampling tubes, and a mechanism for feeding individual tubes from the container to the tube injector mechanism.

6. Apparatus as set forth in claim 4, wherein the support comprises an upright post.

7 Apparatus as set forth in claim 1, including a receptacle for receiving filled sampling tubes released from the tube holding means 8. Apparatus as set forth in claim 7, wherein the receptacle comprises a funnel leading to a container for water.

9. Apparatus for inserting empty sampling tubes into the tube-holding means of an apparatus for taking samples of molten metal, comprising in combination:

injecting means for inserting a sampling tube upwardly into the tube-holding means, said injecting means comprising a cam-actuated rod extending upwardly and adapted to be alternately raised and lowered to insert the sampling tube;

a container connected with the injecting means for holding a plurality of upright sampling tubes in adjacent horizontal relationship to each other; and

feeding means within the container for urging the plurality of tubes horizontally along said container and for feeding each tube individually to the injecting means; said feeding means adapted to be reversed automatically to accommodate additional tubes in the container when the last tube in the container is fed into the injecting means.

10. Apparatus as set forth in claim 9, wherein the cam-actuated rod is vertically adjustable to accommodate tubes of varying lengths. 

1. Apparatus for taking samples of molten metal, comprising a support adapted for positioning between the molten metal to be sampled and a work station at a safe distance therefrom; an elongate arm extending from and secured to said support for pivotal movement thereat about a vertical axis, so said arm can be swung back and forth between the work station and said molten metal; sampling tube-holding means carried by the extended end of said arm; means for swinging said arm about said vertical axis; means for lowering and raising said tube-holding means with respect to the molten metal to be sampled; and means for releasing filled sampling tubes from said tube-holding means.
 2. Apparatus as set forth in claim 1, wherein the means for lowering and raising the tube-holding means comprises a pivotal mounting for the arm on the support for pivotal movement thereat about a horizontal axis, and means for swinging said arm about the horizontal axis.
 3. Apparatus as set forth in claim 1, wherein the support comprises an upright post.
 4. Apparatus as set forth in claim 1, including means at the work station for successively feeding empty, individual, sampling tubes into the tube-holding means.
 5. Apparatus as described in claim 4, wherein the tube-feeding means comprises in combination, a tube-injector mechanism for injecting tubes into the tube-holding means, a container for holding a plurality of empty sampling tubes, and a mechanism for feeding individual tubes from the container to the tube injector mechanism.
 6. Apparatus as set forth in claim 4, wherein the support comprises an upright post.
 7. Apparatus as set forth in claim 1, including a receptacle for receiving filled sampling tubes released from the tube holding means.
 8. Apparatus as set forth in claim 7, wherein the receptacle comprises a funnel leading to a container for water.
 9. Apparatus for inserting empty sampling tubes into the tube-holding means of an apparatus for taking samples of molten metal, comprising in combination: injecting means for inserting a sampling tube upwardly into the tube-holding means, said injecting means comprising a cam-actuated rod extending upwardly and adapted to be alternately raised and lowered to insert the sampling tube; a container connected with the injecting means for holding a plurality of upright sampling tubes in adjacent horizontal relationship to each other; and feeding means within the container for urging the plurality of tubes horizontally along said container and for feeding each tube individually to the injecting means; said feeding means adapted to be reversed automatically to accommodate additional tubes in the container when the last tube in the container is fed into the injecting means.
 10. Apparatus as set forth in claim 9, wherein the cam-actuated rod is vertically adjustable to accommodate tubes of varying lengths. 